re PR fortran/67679 (-Wunitialized reports on compiler-generated variables)

2019-02-03  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/67679
	* trans-array.c (gfc_array_allocate):  For setting the bounds on
	the new array, add a condition for a not previously allocated
	variable.

2019-02-03  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/67679
	* gfortran.dg/warn_undefined_1.f90: New test.
	* gfortran.dg/coarray_lock_7.f90: Fix patterns in test.

From-SVN: r268502

gcc/fortran/trans-array.c

@@ -5736,6 +5736,7 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
   tree var_overflow = NULL_TREE;
   tree cond;
   tree set_descriptor;
+  tree not_prev_allocated = NULL_TREE;
   tree element_size = NULL_TREE;
   stmtblock_t set_descriptor_block;
   stmtblock_t elseblock;
@@ -5882,8 +5883,6 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
 	}
     }
 
-  gfc_start_block (&elseblock);
-
   /* Allocate memory to store the data.  */
   if (POINTER_TYPE_P (TREE_TYPE (se->expr)))
     se->expr = build_fold_indirect_ref_loc (input_location, se->expr);
@@ -5899,6 +5898,19 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
     pointer = gfc_conv_descriptor_data_get (se->expr);
   STRIP_NOPS (pointer);
 
+  if (allocatable)
+    {
+      not_prev_allocated = gfc_create_var (logical_type_node,
+					   "not_prev_allocated");
+      tmp = fold_build2_loc (input_location, EQ_EXPR,
+			     logical_type_node, pointer,
+			     build_int_cst (TREE_TYPE (pointer), 0));
+
+      gfc_add_modify (&se->pre, not_prev_allocated, tmp);
+    }
+
+  gfc_start_block (&elseblock);
+
   /* The allocatable variant takes the old pointer as first argument.  */
   if (allocatable)
     gfc_allocate_allocatable (&elseblock, pointer, size, token,
@@ -5939,6 +5951,11 @@ gfc_array_allocate (gfc_se * se, gfc_expr * expr, tree status, tree errmsg,
       cond = fold_build2_loc (input_location, EQ_EXPR,
 			  logical_type_node, status,
 			  build_int_cst (TREE_TYPE (status), 0));
+
+      if (not_prev_allocated != NULL_TREE)
+	cond = fold_build2_loc (input_location, TRUTH_OR_EXPR,
+				logical_type_node, cond, not_prev_allocated);
+
       gfc_add_expr_to_block (&se->pre,
 		 fold_build3_loc (input_location, COND_EXPR, void_type_node,
 				  cond,

gcc/testsuite/gfortran.dg/coarray_lock_7.f90

@@ -35,8 +35,8 @@ end
 ! { dg-final { scan-tree-dump-times "_gfortran_caf_lock \\(caf_token.., 0, 0, 0B, 0B, 0B, 0\\);" 1 "original" } }
 ! { dg-final { scan-tree-dump-times "_gfortran_caf_unlock \\(caf_token.., 0, 0, 0B, 0B, 0\\);" 1 "original" } }
 
-! { dg-final { scan-tree-dump-times "_gfortran_caf_lock \\(caf_token.., .*\\(\\(3 - parm...dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm...dim\\\[0\\\].ubound - parm...dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm...dim\\\[1\\\].lbound\\)\\), 0, 0B, &ii, 0B, 0\\);|_gfortran_caf_lock \\(caf_token.1, \\(3 - parm...dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm...dim\\\[0\\\].ubound - parm...dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm...dim\\\[1\\\].lbound\\), 0, 0B, &ii, 0B, 0\\);" 1 "original" } }
-! { dg-final { scan-tree-dump-times "_gfortran_caf_unlock \\(caf_token.., .*\\(\\(2 - parm...dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm...dim\\\[0\\\].ubound - parm...dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm...dim\\\[1\\\].lbound\\)\\), 0, &ii, 0B, 0\\);|_gfortran_caf_unlock \\(caf_token.., \\(2 - parm...dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm...dim\\\[0\\\].ubound - parm...dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm...dim\\\[1\\\].lbound\\), 0, &ii, 0B, 0\\);" 1 "original" } }
+! { dg-final { scan-tree-dump-times "_gfortran_caf_lock \\(caf_token.., .*\\(\\(3 - parm....dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm....dim\\\[0\\\].ubound - parm....dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm....dim\\\[1\\\].lbound\\)\\), 0, 0B, &ii, 0B, 0\\);|_gfortran_caf_lock \\(caf_token.1, \\(3 - parm....dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm....dim\\\[0\\\].ubound - parm....dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm....dim\\\[1\\\].lbound\\), 0, 0B, &ii, 0B, 0\\);" 1 "original" } }
+! { dg-final { scan-tree-dump-times "_gfortran_caf_unlock \\(caf_token.., .*\\(\\(2 - parm....dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm....dim\\\[0\\\].ubound - parm....dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm....dim\\\[1\\\].lbound\\)\\), 0, &ii, 0B, 0\\);|_gfortran_caf_unlock \\(caf_token.., \\(2 - parm....dim\\\[0\\\].lbound\\) \\+ \\(MAX_EXPR <parm....dim\\\[0\\\].ubound - parm....dim\\\[0\\\].lbound, -1> \\+ 1\\) \\* \\(3 - parm....dim\\\[1\\\].lbound\\), 0, &ii, 0B, 0\\);" 1 "original" } }
 
 ! { dg-final { scan-tree-dump-times "_gfortran_caf_lock \\(three.token, 0, \\(integer\\(kind=4\\)\\) \\(5 - three.dim\\\[0\\\].lbound\\), &acquired.\[0-9\]+, 0B, 0B, 0\\);|_gfortran_caf_lock \\(three.token, 0, 5 - three.dim\\\[0\\\].lbound, &acquired.\[0-9\]+, 0B, 0B, 0\\);" 1 "original" } }
 ! { dg-final { scan-tree-dump-times "_gfortran_caf_unlock \\(three.token, 0, \\(integer\\(kind=4\\)\\) \\(8 - three.dim\\\[0\\\].lbound\\), &ii, 0B, 0\\);|_gfortran_caf_unlock \\(three.token, 0, 8 - three.dim\\\[0\\\].lbound, &ii, 0B, 0\\);" 1 "original" } }